根据短文内容，选择正确答案。

    With the development of Internet, relative services are developed in the form of websites or apps on phones too. Here introduces you Airbnb and Uber.

    1 Airbnb (air Bed and Breakfast)

People can offer or rent rooms for a short time on Airbnb website or its app on smart phones. The cost is usually cheaper than that of hotels. Travelers can book rooms with special activities such as enjoying local music, art and food.

    Airbnb was founded in August 2008, and now it has over two million listings for travelers to choose in the world. The idea of Airbnb, as its symbol shows, is about home and trust.

    2 Uber

    Uber is a ride sharing and taxi app for fast rides in minutes—day or night. It was founded as Uber Cab in March 2009. The Uber app can send an order to the nearest Uber driver, asking him to the location soon. Users can track the car on their smart phones, so they can know when it will arrive.

In August 2016, Uber service was provided in 507 cities and over 66 countries. However, in China, its operation was acquired by Didi in July 2016. The website Bloomberg View said in July 2015 that Uber makes it easier for people to get a taxi.

阅读理解

    American Sign Language, often called ASL, is used by most people with hearing problems in the United States and Canada.

    Besides ASL, there are more than fifty sign languages used throughout the world today, including Mayan Sign, British Sign, Israeli Sign, and Chinese Sign. Like spoken languages, sign languages are different from each other. But all sign languages are based on sight instead of sounds.

    Sign languages have several main visual (视觉) parts that work together to express meaning. The first part is the shape made by the hands. Movement is also important. Moving the body or organs (器官) like hands affects the meaning of the shape. The place where the sign is made and the direction the hands face are crucial as well. Other visual clues (线索), such as the expression on a person's face, can sometimes change a sign's meaning. For example, a change in a smile can show whether a signer is happy, very happy, or overjoyed. Raising the eyebrows can mark a question.

    In sign languages, the visual parts are combined (结合) in different ways to create signs.

These signs stand for things, actions, feelings, and ideas. ASL has about 4,000 different signs. Like spoken  languages,  sign  languages  cannot  be  translated  word-for-word.  

    For English word may be represented by a series of signs in ASL. Or several English words may be

represented by a single ASL sign. Unlike spoken languages, the signs are organized according to sign-language grammar and the most important word or idea is signed first.

    In ASL, the letter signs are made with one hand. Signers would rarely, if ever, spell out all the words they are signing. That would be as awkward and slow as speakers spelling each spoken word. However, American Sign Language does not have signs for proper names, so signers may use the alphabet to spell these. Also, sign languages often borrow words from other languages. They may spell words using finger spelling which is done with a set of hand shapes that stand for letters of the alphabet.

    Sign languages  develop  naturally  when  people  with  shared  culture  and  needs  want  to communicate with each other. Signers are closely linked to each other, perhaps more than to speaking people in their own communities. Signers share points of view, values, needs, and problems,as well as languages.

    Height is just one of the thousands of features that your genes(基因) decide. In fact, because you have two parents, your genes provide you a height that usually lands somewhere between the height of each parent. If both your parents are tall, then most probably you will be tall, too. But if you have questions about how tall you're going to be, ask your doctor if he or she can help you find it out.

    But genes don't decide everything. For example, eating an unhealthy diet can keep you from growing to your full potential(潜力). Getting plenty of sleep and enough exercise will help you grow to the expected height.

    No doubt you're wondering how fast you should grow. There's no perfect or right answer. Generally speaking, kids grow about two inches(six centimeters) a year between age 3 and the time when they start puberty(青春期).

    Your doctor will know how your growth has been going over the years, how you've been growing up to this point, and what other changes your body may be going through.

    Don't be scared if you seem to have grown a lot in a very short time. Everyone has a growth spurt(高峰) during puberty. The age for starting puberty is about 10 for girls and about 11 for boys. But it can be earlier or later-between 7 and 13 for girls and between 9 and 15 for boys.

    You'll usually begin to notice that you're growing faster about a year or so after your body starts to show the first changes of puberty.

    Have you ever dreamed about sending a letter to yourself or your friends in the future? While express mail(快递) is a fast way to send your letters, there is another type of mail appearing in China as a new business—future mail.

    "The letter should be sent next Mother's Day and not a day earlier!" Lin Xiaofan, a college student in Shanghai, tells one of the companies offering the service.

    Lin Xiaofan wrote the letter to her mother nearly a year earlier to express her love to her mother for next Mother's Day.

    "Offering this service makes people slow down and lets them understand the meaning of 'time' in another way," said Zheng Zhimin, manager at a "future mail" company. Zheng thinks "future mail" letters help remind us of care, friendship and love.

    While "future mail" is becoming more and more popular, some people are wondering what will happen if the postal address changes or if the company goes broken before the letters arrive.

    Zheng said customers are glad to sign a contract(签订合同) to make sure that they can be compensated if their letters are lost or damaged.

    Most of the customers are college students and young white-collar(白领) workers. Psychologists (心理学家) said that young Chinese might have a new way to express their feelings through this service. Most people put their hopes and wishes in the letter so that they can experience the connection(联系) between the past and the present when they receive the letter.